1. Field of the Invention
This invention relates to a compression sleeve for pneumatically applying dynamic pressure to the Achilles tendon, and to the sole of the foot, particularly at the arch.
2. Description of Related Art
Active people commonly experience the ache and debilitating effects of posterior heel pain as a result of three commonly accepted causes: Haglund syndrome, Achilles tendinitis/osis and Sever""s disease.
Haglund syndrome is characterized by a painful soft tissue swelling where the Achilles tendon attaches to the calcaneum (heel bone). Haglund syndrome can often result in the development of a bony deposit on the back of the calcaneum or in the inflammation of the bursa, the fluid filled sac that decreases friction between the Achilles tendon and the calcaneum, which is known as retrocalcaneal bursitis. It is believed that Haglund syndrome results from the repetitive application of trauma or stress to the Achilles tendon.
Achilles tendinitis and tendinosis describe two classifications of tendon injury around the Achilles tendon. Tendinosis refers to non-inflammatory intratendinous degeneration which is initially asymptomatic. Tendinitis describes symptomatic degeneration of the tendon associated with inflammation. Stanish has referred to these tendon classifications as non-union soft-tissue injuries. It is believed that non-union soft-tissue injuries are caused by inadequate perfusion of the local tissues. The affliction is characterized by soft tissue swelling, tenderness to the touch and roughening about the Achilles tendon known as crepitus. Those suffering from Achilles tendinitis/osis also experience pain with active pointing and passive raising of the foot.
Sever""s disease results from a sclerosis or thickening and irregularity of the growth plate known as the calcaneal apophysis. It is believed that Sever""s disease results from inflammation of the soft tissues of the heel following an injury. Sever""s disease may cause a number of conditions including retrocalcaneal bursitis, traction apophysitis, which is the separating of the tendon from the bone, and osteochondrosis of the calcaneal apophysis which is irritation and inflammation of the bone and cartilage in the heel. Those suffering from Sever""s disease experience pain down the back of the heel with passive raising of the foot, rapid and repetitive pointing of the foot and a springy gait. Sever""s disease is aggravated by running and jumping.
These conditions are often treated by use of heel lifts which normally are foam pads approximately 0.25 inches thick; oral pain relievers; shoe inserts; anti-inflammatory medications; rest; ultrasound; various physical therapy treatments; and flexibility exercises. Surgical procedures such as diagonal removal of a heel bone known as oblique calcaneal osteotomy; removal of a deep and superficial retrocalcaneal bursae; cleaning and tendon repair are sometimes required for effective treatment.
Plantar fasciitis is an inflammation of the fascia along the bottom of the foot. The fascia are sheets of fibrous tissue beneath the surface of the skin that enclose muscles or muscle groups and separate muscular layers. Plantar faciitis can be quite painful to an individual but can be soothed by massages that increase circulation to the plantar fascia.
U.S. Pat. No. 4,841,957 in the name of Wooten, et al. describes a U-shaped pad for applying compression around the affected area of the heel. However, the device disclosed in the Wooten patent only applies static pressure to the affected area of the Achilles tendon. We have reason to believe that a dynamic pulsating pressure would be more effective in remedying maladies associated with the Achilles tendon.
Nitric oxide is known to be released with a change in sheer stress in blood flow against the endothelial cells lining the veins. Our studies indicate that pulsating pressure accelerates venous velocity. Other studies show that acceleration of venous velocity increases sheer stress. A recent study, Modulation of Tendon Healing by Nitric Oxide, authored by George A. C. Murrell and others indicates that nitric oxide is present during tendon healing, and that the inhibition of nitric oxide reduces the healing response. While the tendons are avascular, the small nitric oxide molecule is known to pass through vessel walls. Nitric oxide acts as a vasodilator, providing greater fluid and nutrition to local tissues.
The results indicated by testing the present invention supports the belief that application of a dynamic, pulsating pressure around the sides of the Achilles tendon provides relief and healing to those suffering from maladies afflicting the Achilles tendon.
United Kingdom patent No. 817,521 discloses an apparatus for facilitating the blood circulation in the extremities of the human body. The device shown in this patent is cumbersome, making the same difficult and time consuming to attach to the lower leg of the wearer. A further disadvantage in the use of this device resides in the fact that the inflatable cushions must be inflated from an external source, such as a pump.
U.S. Pat. No. 5,348,530 discloses a pneumatic ankle brace with a bladder and foot pump arrangement. The device of this patent is of rather complicated construction and requires use of a detachable hand-held pump.
U.S. Pat. No. 4,841,956 discloses a device adapted to be mounted to the lower leg and foot of a person for inducing venous blood flow in the leg. This device includes a pulse generator and programmable distributor necessitating a non-ambulatory position for the wearer during use.
U.S. Pat. No. 4,678,945 discloses a self-inflating ankle brace including air bags with resilient, compressible filler material. This patent discloses only a brace.
U.S. Pat. No. 6,322,530, assigned to the instant assignee and incorporated herein by reference in its entirety, discloses a wrap made of a plurality of stretchable flexible straps. The straps wrap around the foot to hold in place one aircell positioned in the vicinity of the Achilles tendon and another aircell positioned in the vicinity of the arch of the foot, the two aircells being operatively connected to one another through a conduit member. As the user walks and steps on the aircell at the arch, that aircell is compressed, and the pressure in the aircell at the Achilles tendon is increased. As the user step off the arch aircell, the airflow is reversed, and air travels back from the Achilles tendon aircell to the arch aircell, ready for the next cycle. This device provides effective pneumatic compression of the Achilles tendon, but can be difficult for the user to apply and adjust properly.
The present invention provides relief to those who are suffering from posterior heel pain or from plantar faciitis.
Therefore, an object of the invention is to provide an Achilles sleeve which includes a device for applying pulsating pressure to the Achilles tendon and to the arch area of the foot.
Another object of the invention is to utilize a foot cell to pulse pump pressure to the area around the Achilles tendon.
A further object of the invention is to provide an Achilles sleeve assembly that provides pulsating pressure to the Achilles tendon by use of a aircell that envelopes the Achilles tendon.
An even further object of the invention is to provide an Achilles sleeve assembly having a flexible stretchable sleeve with an inelastic strap around the ankle area to facilitate positioning of the sleeve on the foot and ankle.
The foregoing advantages are achieved by the pneumatic Achilles sleeve assembly of the present invention. The Achilles sleeve assembly comprises a sleeve, the sleeve comprising a foot portion that envelopes the circumference of the foot in the area of the arch of the foot, and an ankle portion that can be opened and closed at the ankle by means of an inelastic strap to allow easy entry of the foot into the sleeve. The foot portion includes a pocket on the inner surface thereof disposed against the arch of the foot, the pocket being configured to accommodate an arch cell that contains a dynamic volume of air. The arch cell is fabricated from a flexible material and is operatively connected to a conduit member. The tendon cell is shaped to envelop the sides of the Achilles tendon and is disposed on the rear inner surface of the ankle portion of the sleeve. The tendon cell also is operatively connected to the conduit member. Upon application of external pressure to the arch cell, air is expelled from the arch cell through the conduit member and into the tendon cell.
Both the tendon cell and the arch cell are fabricated from a flexible material defining pockets containing open-cell foam pads. When air is expelled from said arch cell, the air passes through the conduit member into the tendon cell which exerts a greater pressure against the Achilles tendon. The arch and tendon cells are self-inflating. Thus, an external pump is not required.
A better understanding of the present invention and its objects and advantages can be had by making reference to the following detailed description taken in conjunction with the accompanying drawings.